R E S E A R C H Open AccessMotivation for smoking cessation among drug-using smokers under methadone maintenance treatment in Vietnam Bach Xuan Tran1,2*†, Long Hoang Nguyen3†, Huyen Phuc
Trang 1R E S E A R C H Open Access
Motivation for smoking cessation among
drug-using smokers under methadone
maintenance treatment in Vietnam
Bach Xuan Tran1,2*†, Long Hoang Nguyen3†, Huyen Phuc Do4, Nhung Phuong Thi Nguyen5, Huong Thu Thi Phan6, Michael Dunne4and Carl Latkin2
Abstract
Background: Smoking cessation treatment service is concerned to be a critical element in methadone
maintenance treatment (MMT) in order to diminish the effect of smoke on health outcomes To implement the smoking cessation services in Vietnam, we examined the stages of change to quit and determined associated factors among MMT patients
Methods: We conducted a cross-sectional survey with 1016 MMT patients in five clinics in Hanoi and Nam Dinh province, of those, 932 (91.7 %) were ever-smokers Patients were classified into four groups:“pre-contemplation,”
“contemplation,” “preparation,” and “action and maintenance” by using the transtheoretical model Multivariate logistic regression was applied to determine the associated factor for intention and action to quit smoking
Results: Overall, 96 % were not actively trying to quit or maintain abstinence Age older than 45, HIV-positive
status, and residence in Hanoi were negatively associated with intention to quit Meanwhile, higher levels of
nicotine dependence and number of years of smoking negatively associated with quitting and abstinence
Conclusions: The study indicated the high rate of MMT smokers being in pre-contemplation stage but low
proportion of quitting and maintaining abstinence It emphasizes the importance of availability and accessibility of information about smoking cessation therapies and services Integrating cessation programs into health-care
services should be considered to provide tailored interventions for different patient groups
Keywords: Smoking, Cessation, Stage, Change, Methadone, MMT, Drug use, Vietnam
Background
Improving health status and supporting healthy
behav-iors are the goals of interventions for people who inject
drugs (PWID) [1] As a country experienced a rapid
spread of HIV infection in drug-using populations,
Vietnam has been implementing a comprehensive harm
reduction strategy [2] First introduced in 2008,
metha-done maintenance treatment (MMT) service has become
an essential component of the National HIV/AIDS
Strat-egy [2] Previous studies have shown that MMT is
cost-effective in preventing new HIV cases, improving HIV/
AIDS treatment outcomes, and relieving the economic burden of HIV/AIDS and substance abuse on both health systems and affected households [3–5] MMT, therefore, is the primary intervention that engages IDU into harm reduction programs and health-care services Although drug-use behaviors significantly changed over the course of MMT, other unhealthy behaviors may result in diminished health status and quality of life in this patient group [6] Despite decreasing prevalence of smoking in general population (56 %), it remains high among MMT patients (from 71 to 98 %) [7–10] In de-veloped countries, some MMT programs have instituted smoking bans, which has reduced the proportion of staff who smoke but not proportion of patients [11] Evidence showed that an interaction between methadone and nicotine might increase euphoria and diminish mental
* Correspondence: bach@hmu.edu.vn
†Equal contributors
1 Institute for Preventive Medicine and Public Health, Hanoi Medical
University, Hanoi, Vietnam
2 Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
Full list of author information is available at the end of the article
© 2015 Tran et al Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made The Creative Commons Public Domain Dedication waiver
Trang 2problems such as restlessness, irritability, and depression
[12], by which maintains smoking and reduces patients’
attempts to quit [7] This interaction is considered a
major cause of morbidity, mortality, disability, and
poorer quality of life among opioid-dependent
smokers compared to non-smokers [13–15] Therefore,
attention should be paid on smoking among PWID,
and cessation interventions should be encouraged during
MMT [15–18]
Understanding motivation to quit smoking may help
predict success of cessation [19, 20] This is more
im-portant among drug users who reported much lower
success rate in quitting smoking (12–22 %) than general
population (48–58 %) [7–9, 21–23] Previous studies
have shown a number of individuals and environmental
factors that influence the process of adapting and
main-taining smoking abstinence among PWID These factors
included socioeconomic status, mental health problems,
unavailability of health services, family supports, peer
in-fluences, and cultural acceptability [23, 24] Given its
high variation across settings, empirical evidence of
con-textual factors are necessary to design effective smoking
cessation programs for PWID
The rapid expansion of MMT services in Vietnam has
provided the treatment to over 30,000 patients [25, 26]
Although the prevalence of smoking among men in
Vietnam was high, however, understanding of smoking
and motivation to quit among MMT patients are still
limited In this study, we sought to assess patients’
mo-tivation to quit smoking and its associated factors over
the course of MMT in a multi-site survey
Methods
Study design and sampling technique
A cross-sectional survey was conducted during January
to August 2013 in two northern provinces: Hanoi and
Nam Dinh Five MMT clinics were purposely selected
including (1) provincial and district sites, (2) in both
rural and urban areas, and (3) different integrative
models (Table 1) We invited all patients who registered
for MMT at the selected sites to participate in the survey
Eligibility criteria for recruiting participants included (1)
taking or initiating MMT in selected sites, (2) presenting
at clinics during study period, (3) being 18 years old or
above, (4) having capacity to answer questionnaire, and (5) agreeing to participate A total of 1016 patients (91.5 % response rate) were interviewed, of those, 932 (91.7 %) re-ported ever smoked that formed the subgroup of this ana-lysis In a designated room, face-to-face interviews were carried out by well-trained investigators using a structured questionnaire for about 30 min
Measurements
Variables of interest were selected by adopting the socio-contextual model of Sorensen et al for reducing tobacco use among blue-collar workers [27] In this study, we measured the influence of patient- and provider-related factors on motivation and readiness to quit smoking among MMT patients
Socioeconomic status
Socioeconomic factors including age, gender, marital sta-tus, education, occupation, religion, and income were in-vestigated Income per month per capita was computed
by summing all monthly income sources of household, then dividing to the number of household’s members
Health-related quality of life
Health status was measured using EQ-5D-5L instru-ment which showed good measureinstru-ment properties in Vietnamese settings [28] EQ-5D-5L contains five di-mensions (mobility, self-care, usual activities, pain/dis-comfort, and anxiety/depression) with five response levels [29] In addition, body mass index and HIV sta-tus were recorded
Health-care and MMT service utilization
The use of inpatient and outpatient health services over the past 12 months and duration on MMT were self-reported
Substance abuse
To assess alcohol use, we employed a brief version of the alcohol use disorders identification test-consumption (AUDIT-C) instrument [30] The Vietnamese version has been used in previous studies [31, 32] It is comprised
of questions with a total score of 0–10 Higher scores indicate higher risks of alcohol dependence Hazardous
Table 1 Study settings and sample size
VCT voluntary HIV testing and counseling, ART antiretroviral treatment, GH general healthcare
Trang 3drinkers are identified with the threshold of 4 or above for
men and 3 or above for women [30, 33] Additionally,
binge drinkers are determined if the respondents have any
positive response to the third question Illicit drug use
be-haviors included history and current opioid use, duration
of drug use, and the experience of previous drug treatment
Smoking-related characteristics
To understand the motivation to quit smoking of MMT
patients, we applied the transtheoretical model that
de-scribes the progressing of health behaviors through a
series of five sequential stages of change This includes (1)
pre-contemplation→ (2) contemplation → (3)
prepar-ation→ (4) action → (5) maintenance We asked the
pa-tients a question: “Are you thinking about quitting
smoking?” with four response levels: “No thought of
quit-ting,” “Think I should quit but not quite ready,” “Starting
to think about how to change my smoking behavior,” and
“Take action to quit” corresponding to the stages of
(1)→ (4) The stage (5) maintenance included those who
have been abstinent of smoking over 6 months
In addition, the Fagerström test for nicotine
depend-ence (FTND) was used to assess the levels of nicotine
dependence among patients This instrument contains
six items that yield a total score of 0–10 Higher score
indicates higher level of dependence [34] Based on the
score, patients were classified into following groups: 0–2:
very low, 3–4: low, 5: moderate, 6–7: high, and 8–10: very
high Other indicators, including smoking duration,
expenses, and number of cigarettes per days, were also
recorded In addition, we asked patients who thought of
quitting or cutting down the number of cigarettes they
smoke what measures or supports they would like to
receive to take action and maintain abstinence
Data analysis
The p value <0.05 was considered statistically
signifi-cance.T test, ANOVA test, and χ [2] were used to
meas-ure the difference between means and proportions To
identify the determinants of intention and taking action
to quit smoking, we employed multivariate binominal
lo-gistic regression, with fractional polynomial model for
duration of MMT treatment, to assess the non-linear
re-lationships among variables In addition, backward
step-wise model was approached to include variables with the
threshold of p values of log-likelihood ratio test <0.2
We then displayed the results by odd ratios (OR) with
corresponding 95 % CI Data analysis was performed by
using STATA software version 12.0 (Stata Corp LP,
College Station, United States of America)
Ethical approval
This study was approved by the Vietnam Authority of
HIV/AIDS Control’s Scientific Research Committee
Written informed consents were collected before start-ing the interview Respondents could withdraw from the study at any time The information of patients was coded to ensure confidentiality
Results
Of 932 respondents, the mean age of sample was 36.5 years (SD = 7.4) The predominant groups were male (98.8 %), with a religious orientation of cult of an-cestors (88.7 %), and living with spouse/partner (66.7 %) Most of the respondents attained less than high school (54.3 %) and had employment (74.3 %) The majority of the participants had income more than 2.5 million VND per month (43.6 %) (Table 2) Table 2 also shows the health status and health-care utilization of patients There were 7.9 % of respondents who were HIV-positive and 6.3 % currently taking ART medication Based on the EQ-5D-5L, about one fifth of sample reported anxiety/ depression (20.2 %) and 17.1 % felt pain/discomfort About 22 % had used outpatient health-care service in the last 12 months, while 8.3 % used inpatient services Table 3 indicates substance-use behaviors among MMT patients More than a half of respondents smoked over 10 cigarettes per day The proportions of people smoking within 5 min of waking and even if sick in bed were 32.8 and 0.9 %, respectively About half of respon-dents reported a moderate to very high levels of nicotine dependence The mean age of initial smoking were 17.2 (SD = 3.5), and the mean duration of smoking was 14.1 years (SD = 8.5) On average, participants spent 300 thousand Vietnam dong (~USD 15, 2013 exchange rate) monthly for tobacco
Table 3 also shows that the mean age of initial drug use was 24.4 years (SD = 6.5) There were 74.7 % respon-dents ever injected drug, and 4.8 % of patients were con-currently using opiates during MMT Most of the samples had one to five episodes of drug rehabilitation (66.0 %) As for alcohol use, the prevalence of hazard and binge drinking was 57.1 and 53.5 %, respectively There was only 4 % currently taking actions to quit smoking, meanwhile 22.1 % were in preparation stage and 22.8 % were in contemplation stage where they thought of quitting In Table 4, preference for cessation supports were explored among those who were aware of the harms of smoking (n = 455) Of 423 responses (93 %), self-administration without others’ supports was the most preferable approach for smoking cessation among MMT smokers (77.6 %), followed by using nico-tine replacement therapy (11.3 %) and having familial (5 %) and health workers’ (4.5 %) supports
Results from reduced multivariate logistic regression are shown in Table 5 The intention to quit smoking of MMT patients was negatively associated with age older than 45, HIV-positive status, and residence in Hanoi,
Trang 4Table 2 Demographic, health status, and health-care utilization of respondents
Marital status
Educational attainment
Employment
Religion
Income per capita
Location
Area of clinics
MMT model
Health-related status
Body mass index
Health-care services utilization in the last 12 month
Trang 5while positively associated with having outpatient
health-care services in the last 12 months As for
quit-ting and maintenance, we found that the level of
nico-tine dependence and longer years of smoking negatively
predicted quitting and maintaining abstinence among
MMT patients In these models, the duration on MMT
has been treated as a polynomial factor that showed a
negative association between the number of months on MMT and the likelihood of smoking abstinence; how-ever, it was not statistically significant
Discussion
This is the first study investigating factors associated with the motivation of MMT patients to quit smoking in
Table 3 Smoking, nicotine dependence and other substance abuse
Pre-contemplation
Contemplation Preparation Action and
maintenance
Smoking
Number of cigarettes per day
Nicotine dependence level
Expense for smoking (thousand VND per month) 302.26 312.5 289.59 272.5 310.03 259.1 140.59 185.2 294.68 289.6 <0.01
Drug use
# drug rehabilitation
Alcohol use
Trang 6Vietnam Using the transtheoretical model, we charac-terized the stages that MMT patients are in with regard
to their smoking behaviors The findings showed a sub-stantial proportion of MMT patients were at the pre-contemplation stage They did not have any intention to change their smoking behaviors It is important to note that intentions to quit and taking action to quit smoking were not improved over the course of MMT
In this study, 44.9 % respondents were in the contem-plation and preparation stages and only 4.0 % took ac-tion to quit smoking and maintained abstinence These figures were lower than previous studies in MMT pa-tients For example, a study of Nahvi et al showed that
48 % of MMT smokers were in contemplation stage and
22 % were in preparation stage [9] Another study of Richter et al suggested that 46 % of MMT patients were
in contemplation stage [35] Since having an intention to
Table 4 Preference for support among MMT patients who
thought of smoking cessation
Table 5 Factors associated with Intention to quit and quitting smoking
Religion (vs cult of ancestors)
Occupation (vs unemployed)
Age (vs 18 –<25)
Marital status (vs single)
Income quintile (vs poorest)
HIV status (vs negative)
Body mass index (vs underweight)
Level of nicotine dependence (vs very low)
*p < 0.1; **p < 0.05; *** p < 0.01
Trang 7quit smoking may predict successful smoking abstinence
[36], the low rate of intention to quit smoking in the
present study may reflect the lack of smoking cessation
interventions and antismoking campaigns targeting this
population For MMT patients, as illicit drug use is
highly stigmatized in Vietnam, it is likely that their focus
is on opiate absences and do not view cessation of
to-bacco use as a priority Moreover, smoking is normative
among men in Vietnam with over half of the adult male
population currently smoking
Literatures documented that patients might suffer
from withdrawal problems (stress/anxiety or other
men-tal problems) while attempting to quit smoking [37] due
to nicotine dependence [38] In our study, higher level of
nicotine dependence and number of years of smoking
were negative predictors of patient’s abstinence to
smok-ing [39, 40] This is similar to findsmok-ings by John et al who
also suggested that nicotine dependence may increase
the number of quit attempt but decrease the likelihood
of abstinence [38] As for preferred supports for smoking
cessation, the majority of respondents chose
self-administration while having cessation-related health was
very limited It may be because of the unawareness of
smokers and unavailability of smoking cessation services
as well as other socioeconomic barriers [41]
Noticeably, the duration of MMT was inversely related
to the intention, although this association was not
statistical significance To date, prior studies have not
examined this association Since the duration of MMT
treatment was proportionate with the reduction of MMT
doses, patients with lower doses of methadone were more
likely to report quit intensions [9] Additional research to
investigate the interaction between duration of MMT and
MMT doses on readiness to quit smoking is warranted
This study suggested several implications First,
clini-cians should understand MMT patients’ stage of change
for smoking cessation in order to implement tailored
counseling and interventions They should first ask
about smoking in MMT clients, then ask about their
interest in quitting Patients who report no interest
should be counseled using motivational interviewing
about dangers of smoking and ability for people to quit
Those who express interest should be provided with a
brief smoking cessation intervention, the “five A’s,”
in-cluding ask, advise, assess, assist, and arrange [42]
These tailored clinical interventions should be coupled
with community level interventions [41] Second,
pro-viding smoking cessation treatment by integrating into
MMT clinics (on-site program) may encourage the
mo-tivation for smoking cessation Besides, for those
smokers taking antiretroviral therapies, intervening on
smoking may also improve treatment adherence and
outcomes [43] Finally, capacity of health staffs in terms
of screening and counseling should be enhanced by
training, which helps to enhance the provision of smok-ing cessation treatment [41]
The strengths of this study included a large sample of MMT patients in various Vietnamese settings In addition,
we employed several measures (EQ-5D-5L, FTND, AUDIT-C) that showed good measurement properties in these patient groups in Vietnam [3, 28, 31, 32, 44, 45] Nonetheless, some limitations should be acknowledged First, causal relationships between motivation to quit and related factors cannot be established due to the cross-sectional design Second, data collection was based on self-reports, which might lead to recall bias Finally, some psychosocial factors such as methadone dose, self-efficacy, depression, tobacco availability, social norms, and smoking cost data were not collected, suggesting the further research to investigate those factors in order
to better understand the mechanism of smoking be-haviors and develop appropriate interventions
Conclusions
In conclusion, the study indicated the high rate of MMT smokers being in pre-contemplation stage but low proportion of quitting and abstinence This study also underlined the importance of availability and accessibility
of information about smoking cessation therapies with the high-quality consultation and services Integrating ces-sation programs into health-care services should be considered to provide tailored interventions for different patient groups
Competing interests The authors declare that they have no competing interests.
Authors ’ contributions BXT, HTTP, CL conceived of the study, and participated in its design and implementation and wrote the manuscript LHN analyzed the data BXT, LHN, HPD, HTTP, CL, MD helped to draft the manuscript All authors read and approved the final manuscript.
Acknowledgements The authors would like to acknowledge supports by the Vietnam Authority
of HIV/AIDS Control for the use of this survey data There was no funding for this analysis.
Author details
1 Institute for Preventive Medicine and Public Health, Hanoi Medical University, Hanoi, Vietnam.2Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA 3 School of Medicine and Pharmacy, Vietnam National University, Hanoi, Vietnam.4School of Public Health and Social Work, The Queensland University of Technology, Brisbane, Australia 5 Hanoi University of Pharmacy, Hanoi, Vietnam.6Authority of HIV/AIDS Control, Ministry of Health, Hanoi, Vietnam.
Received: 8 August 2015 Accepted: 27 October 2015
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